drbd: Force flag for the detach operation

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

3 files changed, 19 insertions, 2 deletions

diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 1b59ab3ab9c7..bc8a8a7556da 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -495,7 +495,7 @@ static int cl_wide_st_chg(struct drbd_conf *mdev,
                  ((os.role != R_PRIMARY && ns.role == R_PRIMARY) ||
                   (os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
                   (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S) ||
-                  (os.disk != D_DISKLESS && ns.disk == D_DISKLESS))) ||
+                  (os.disk != D_FAILED && ns.disk == D_FAILED))) ||
                 (os.conn >= C_CONNECTED && ns.conn == C_DISCONNECTING) ||
                 (os.conn == C_CONNECTED && ns.conn == C_VERIFY_S);
 }
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index cabad39f908c..6d116a2b2321 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -1337,17 +1337,32 @@ static int drbd_nl_detach(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
 {
         enum drbd_ret_code retcode;
         int ret;
+        struct detach dt = {};
+
+        if (!detach_from_tags(mdev, nlp->tag_list, &dt)) {
+                reply->ret_code = ERR_MANDATORY_TAG;
+                goto out;
+        }
+
+        if (dt.detach_force) {
+                drbd_force_state(mdev, NS(disk, D_FAILED));
+                reply->ret_code = SS_SUCCESS;
+                goto out;
+        }
+
         drbd_suspend_io(mdev); /* so no-one is stuck in drbd_al_begin_io */
         retcode = drbd_request_state(mdev, NS(disk, D_FAILED));
         /* D_FAILED will transition to DISKLESS. */
         ret = wait_event_interruptible(mdev->misc_wait,
                         mdev->state.disk != D_FAILED);
         drbd_resume_io(mdev);
+
         if ((int)retcode == (int)SS_IS_DISKLESS)
                 retcode = SS_NOTHING_TO_DO;
         if (ret)
                 retcode = ERR_INTR;
         reply->ret_code = retcode;
+out:
         return 0;
 }
 
diff --git a/include/linux/drbd_nl.h b/include/linux/drbd_nl.h
index ab6159e4fcf0..7203c9ead233 100644
--- a/include/linux/drbd_nl.h
+++ b/include/linux/drbd_nl.h
@@ -33,7 +33,9 @@ NL_PACKET(disk_conf, 3,
         NL_BIT(         58,     T_MAY_IGNORE,   no_disk_drain)
 )
 
-NL_PACKET(detach, 4, )
+NL_PACKET(detach, 4,
+        NL_BIT(         88,     T_MANDATORY,    detach_force)
+)
 
 NL_PACKET(net_conf, 5,
         NL_STRING(      8,      T_MANDATORY,    my_addr,        128)